It isn't an easy job , best left to garage .See here ,
2002 318i N42 crankshaft sensor.
I am due to change my crankshaft sensor tomorrow due to the usual cutting out every now and then etc that is associated with a failing crankshaft sensor.
My question is this.
Has anyone changed one on the N42 and can give me a few pointers of what im up against. I.e what tools i may need and what to take off to get to it.
I have a good socket set and a set of torx sockets so im fairly well preppared.
Please dont confuse this with the easy to get to get to sensor on the M43 etc as i know the inlet manifold definately has to come off to gain access.
Cheers in advance.
View Public Profile
Send a private message to crespo
Find all posts by crespo
#2 09-10-2010, 00:33
crespo's Car Specifications
crespo's Car Specifications
Make of Car: BMW
Model of Car: 318i se
Year of Vehicle: 2001
Transmission Type: Manual
Car Body Type: Saloon
Join Date: Sep 2010
Thanked 27 Times in 25 Posts
Found this post while searching the net. I thought i would post it here incase anyone else is going to attempt it.
It is a fairly long job, took me several hours but being careful helps. You need a torque wrench, a set of common sockets and spanners, a set of 1/4" drive sockets, a set of hex bits, and a set of small-size torx bits or keys. A lot of stuff comes off, so have a clean bench to put it all down on. You really need to have a good manual such as TIS or the Haynes manual, I have both and they were both useful. You have to get under the car so need ramps too. First clean the top of the engine well to remove dust etc to avoid it going down into the injector holes and the intake ports. Depressurise the fuel tank to avoid spraying petrol around when you disconnect the fuel pipe. Also disconnect the battery!
Generally a straight-forward job with a few awkward bits.
The whole intake manifold has to come off. Take off all of the air intake assembly and all of the stuff above the rear of the motor, which is the micron filter housing - looks daunting but is fairly simple. The hardest part I found to be removing one of the screws which hold the intake manifold on to the manifold support bracket, because my car has air conditioning (maybe you don't need it in your part of the world) and the compressor gets in the way. There are two screws, the one at the back is easy since you can see it from under the car but need a very long socket extension to get the torx bit up to the screw. To get it back in later use a magnetic bit holder or tape it on with sticky tape. The front one is a b*gger with the aircon compressor restricting access from below, so you have to do it from above and there is almost no room below the screw to get the torx bit in and turn it. It helps to have very small hands and my neighbour's daughter was a big help! When replacing it I used a hex head bolt, since it was a lot easier to tighten from above, and would be easier to remove in future. If you don't have air it should be easy from under the car I think. Also, remove or at least loosen the dipstick tube to allow the manifold to come off and go back on more easily - the TIS manual does not show this.
The fuel injectors were a bit sticky but came off with gentle leverage with a screwdriver. The connectors are fiddly, and the Jesus clips holding them on can fly away! The manifold lifts off vertically but was sticky too. Check the port seals and replace if any suspicion about condition.
Replacing the crank sensor itself is easy (a bit of an anticlimax), just above the starter motor, the screw is Loctited in so needs a bit of a twist to undo.
Clean the surface around the head ports with a bit of kerosene if it is even slightly dirty. Don't wipe stuff into the ports.
Replacing the manifold, take extra care to have the port seals securely in place in the manifold or you will have to do it all over again. ie they can fall out as you put the manifold on. But they do hang on in the manifold pretty well if you put them in carefully. If they don't then get new ones. Getting the manifold back on is almost impossible if you don't loosen the dipstick tube. You have to put the manifold back on while holding the oil separator assembly on below it - it has to slot into place into guides on the underside of the manifold assembly, but it just seemed to slide into place easily when I did it. The TIS manifold says you need special tools to do this (Haynes does not), and I was worried about this but it was easy. Using both hands at front and back and holding up the separator to the manifold seemed to do the trick. Torque the nuts etc down.
Keep the injectors clean when replacing them, use a very small amount of silicone grease to lubricate the O-rings.
Replace the screws under the manifold support (see above for advice). After that it is easy. I was a bit nervous while doing all this because I kept imagining that it would never go again and I would have to tow it down to the BMW experts, but it went first twist of the key.
My car has been fine since I did this, which is about 1000 km or so by now.
Good luck with it.
The Following User Says Thank You to crespo For This Useful Post:
Posted on Saturday 13th of November 2010Don't understand this? Ask a question